Offset drilling tool



Aug. 27, 1940. H. w. EVANS OFFSET DRILLING TOOL Filed Feb. 6, 1939 IWB.

INVEN Ton. Hanny Win/fs Eva/vs.

mllw||L FILI llllllll IlxvTl Patented Aug. 27, 1940 PATENT OFFICE OFFSET DRILLING TOOL Harry Willis Evans, Anaheim, Calif., assigner of one-half to H. John Eastman, Long Beach,

Calif.

Application February 6, 1939, Serial No. 254,853

10 Claims.

'I'his invention relates to an offset Idrilling tool, by means of which the direction of a bored hole is changed in order to straighten or deflect the hole, as desired.

An object of my invention is to provide a novel means of setting and releasing a sleeve within the bored hole, by means of the relative longitudinal movement of a mandrel to this sleeve.

A further object is to provide a novel offset drilling tool of the character stated, in which a slidable driving means is provided between the mandrel and the bit, whereby the bit may advance into the formation after the tool has been set in the hole.

l5 Still another object is to provide a, novel offset drilling tool, in which the releasing lug is automatically directed to releasing position on upward movement of the mandrel.

Still another object of my invention is to provide a tool of the character stated, which is effective in operation and which can be easily operated by the average workman on a drilling rig.

Other objects, advantages and features of invention may appear from the accompanying drawing, the subjoined detailed description, and the appended claims.

In the drawing:

Figure 1 is a longitudinal, sectional View of my onset drilling tool, with the parts in position as when the tool is being moved into the bored hole. i

Figure 2 is a side elevation of my oiset drilling tool with parts broken away to show interior construction, the parts being arranged as when the dog or slip is released for engagement with the side of the bored hole.

Figure 3 is a side elevation of my tool, showing the parts in position for drilling forwardly in the formation.

Figure 4 is a fragmentary, longitudinal, sectional view of the sleeve, showing the slot and the cam surfaces, which guide the releasing lug into position. Figure 5 is a fragmentary, side elevation of the actuating mandrel, showing the releasing lug.

Figure 6 is a sectional View taken on line 6-6 of Figure 2.

Figure 7 is a sectional view taken on line 'I-I of Figure 2.

Referring more particularly/to the drawing, the numeral I indicates a sleeve, which is provided with a central bore 2,'adapted to receive the mandrel 3. The mandrel 3 is slidable in I the sleeve I, and in certain positions of said (Cl. Z-1) mandrel is rotatable in the sleeve. Anti-friction bearings 4-4 may be provided within the sleeve, around the mandrel 3, so that this mandrel will easily rotate in vorder to drill forwardly in the formation, as will be further described. The 5 mandrel 3 is provided with a releasing lug 5 on the side thereof, the purpose of which will be further described.

The sleeve I is provided with a vertical slot 6, which extends through the side wall of the 10 sleeve and into the bore 2. A dog or slip 'I is movably mounted in the slot 6 and is adapted to be exten-ded or retracted into the sleeve I in order to non-rotatably mount the sleeve in the bored hole, or to release said sleeve for verticalv 15 movement, as may be desired. A spring 3 is attached at one end to the slip inthe other end of this spring being ixedly attached to the sleeve I. This spring constantly urges the slip 'I into retracted position, as shown in Figure l. The 20 slip 'I is moved outwardly into engagement with the wall of the bored hole by a cam dog 9, which is slidably mounted for vertical movement in the slot 6. A spring I0 urges the cam dog downwardly against the inner surface of the slip 'I 25 for the purpose of urging this slip outwardly against the wall of the bored hole. When the slip 'I and the dog 9 are in position to extend the slip, the mandrel 3 engages the dog as shown in Figure 2 to hold the dog against the slip and 30 thus hold this slip tightly in engagement with the wall of the bored hole.

For the purpose of directing the lug 5 into the slot 6, irrespective of the position of the lug 5, I provide a double inclined cam I I, which extends 35 downwardly from the loweredge ofthe slot 6, substantially as shown in Figures l, 2 and 4. Thus, when the mandrel 3 is pulled upwardly, the cam Il will tend to rotate the mandrel, and direct the lug 5 into the bottom of the slot 6. A roller I2 might be provided at the top of the lug 5 so that this rotating action is more easily accomplished.

A driving post I3 depends from the mandrel 3 and this driving post is preferably angular in 45 cross-section, as shown in Figure 6, so that it is both slidable and non-rotatable in a sub I4. A head I5 on the lower end of the post limits the upwardrmovement of the post in the sub I4. The bit I6 is mounted on the lower end of the sub I4 either directly or is coupled to the s'ub by the pipe l'l. Itfis understood that the drill pipev I8 is attached to the upper end 0f the mandrel 3. In operation, the tool is mounted on the lower end of the drill pipe, and the weight 55 of the sleeve I, sub III, and bit I 6 will hold the parts in the position shown in Figure 1, namely,

with the mandrel 3 slid upwardly as iar as it will move. In this top position of the mandrel., the lug 5 holds the dog 9 Aat the top of the slot B, thus permitting the spring 8 to force the slip 'I inwardly, permitting the tool a free passage into the bored hole. When the bottom of `the hole is reached, the bit I6 rests on the bottom. and thereafter the operator allows the drill pipe I 8 to move downwardly, thus carrying the mandrel 3 downwardly through the sleeve I, because of the slidable mounting of the post I3 in the sub It; The dog 9 is nowreleased and the slip 'l is pressed outwardly against the side of the bored hole, as shown inFigure 3. The drill pipe I8 is now rotated, thereby rotating the bit I6 through the driving sub I4. The mandrel 3 can continue to advance through the sleeve I, and furthermore the post I3 will permit longitudinal movement of the sub Ill relative to the mandrel 3. The hole will-be deflected at an angle. from that previously drilled, due to the fact that the sleeve I ispressed to one side of the hole by the action of the slip This induces a bow in the drilling string, thus deflecting the hole from the course previously drilled.

It will be noted that when the mandrel 3 moves downwardly relative to the sleeve I, that the tapered surface of the lug 5 will force the slip 1 outwardly, thus permitting the dog 9 to drop back of this sleeve and hold the same tightly in engagement with the .wall of the hole.

Having described my invention, I-claim:

1.'An oiset drilling tool comprising a sleeve, a mandrel mounted for longitudinal movement in the sleeve, wall engaging means mounted on .the sleeve and adapted when moved outwardly to engage the wall of a bored hole, means on the mandrel adapted and arranged to engage the wall engaging means on longitudinal movement of said mandrel whereby said wall engaging means is urged outwardly against the wall of a bored hole, a bit operatively connected to said mandrel and rotatable therewith, and means in the sleeve adapted and arranged to engage and lock said wall engaging means as Said wall engaging means is pressed outwardly, whereby said Wall engaging means is held in engagement with the wall of a bored hole.

2. An oiset drilling'tool comprising a sleeve, a mandrel rotatably and slidably mounted in said sleeve, a slip mounted on the sleeve, said sleeve having a Slot in the side thereof into which said yslip is adapted to extend, means on the mandrel extending into said slot and engageable with the slip to.urge said slip outwardly, locking means in the sleeve engageable with the slip on outward movement of said slip to hold the same in extended position, cam means in the sleeve extending to said slot whereby said slip engaging means is returned to said slot on upward movement of the mandrel, and a bit operatively connected to said mandrel.

3. An olset drilling tool comprising a sleeve, a mandrel rotatably and slidably mounted in said sleeve, a slip mounted on the sleeve, said sleeve having a slot in the side thereof into which said slip is adapted to extend, means on the mandrel extending into said slot and engageable with the slip to urge said slip outwardly, locking4 means in the sleeve engageable with the slip on outward movement of said slip to hold the same in extended position, cam means inthe sleeve extending to said slot whereby said slip engaging means is returned to said slot on upward movement of the mandrel, a bit mounting operatively connected to said mandrel, and a longitudinally slidable driving means connecting said mandrel and the bit mounting.

4. An offset drilling tool comprising a sleeve, a mandrel slidably and rotatably mounted in said sleeve, said sleeve having a slot in the side thereof, a wall engaging slip mounted on the sleeve and extending into said slot, a lug on the mandrel vengageable with theV slip to extend the same, a dog mounted in said slot and engageable with the slip as the slip is extended, whereby the slip is held in extended position, and a bit operatively connected to said mandrel.

5. An offset drilling tool comprising a sleeve, a mandrel slidably and rotatably mounted in Said sleeve, said sleeve having a slot in the side thereof, a wall engagingv slip mounted on the sleeve and extending into said slot, a lug on the mandrel engageable with the slip to extend the same, a dog mounted in said slot and engageable with .the slip as the slip is extended, whereby the slip is held in extended position, abit mounting operatively connected to said mandrel, and longitudinally slidable drive means connecting said mandrel and the bit mounting.

6. An offset drilling` tool comprising a sleeve, a mandrel slidably and rotably mounted in said sleeve, said sleeve having a slot in` the side thereof, a wall engaging slip mounted on the sleeve and extending into said slot, a lug on the mandrel engageable with the slip to extend the same, a dog mounted in said slot and engageable with the slip as the slip is extended, whereby the slip is held in extended position, a bit mounting operatively connected to said mandrel, longitudinally slidable drive means connecting said mandrel and the bit mounting, and a cam surface in the sleeve extending to said slot whereby the lug is moved4 into the slot on upward movement of y the mandrel.

7. An olset drilling tool comprising a sleeve, a mandrel rotatably and slidably mounted in the sleeve, said sleeve having a slot in the side thereof, a slip projecting into the slot, spring means engaging the slip and urging the same into the slot, a lug on the mandrel engageable with the slip on longitudinal movement of the mandrel and urging said slip outwardly, a locking dog engageable with the slip in extended position thereof, whereby the slip is held against the wall of a bored hole, a sub, a bit mounted on the sub, a driving post depending from the mandrel, said driving post being slidable and non-rotatable in the sub.

8. An offset drilling tool comprising a sleeve, a mandrel rotatably and slidably mounted in the sleeve, said sleeve having a slot in the side thereof, a slip projecting into the slot, spring'means engaging the slip and urging the same into the slot, a lug on the mandrel engageable with the slip on longitudinal movement of the mandrel and urging said slip outwardly, a locking dog engageable with the slip in extended position thereof, whereby the slip is held against the wall of a bored hole, a sub, a bit mounted on the sub, a

'into the slot on upward movement of the mandrel.

9. An offset drilling tool comprising a sleeve, a mandrel rotatably and slidably mounted in 4said sleeve, a-slip mounted on the sleeve, said vsleeve having a slot in the side thereof into which 4 said slip is adapted to extend, means on the mandrel extending into said slot and engageablerwith the slip to urge said slip outwardly, locking means in the sleeve engageable with the slip on outward movement of said slip to hold the same in extended position, means on the mandrel engageable with said locking means on upward movement of the mandrel, whereby said locking means'is released to permit inward movement of said slip.

10. An oii'set drilling tool comprising a sleeve, a mandrel rotatably and slidably mounted in said sleeve, a slip mounted on the sleeve, said sleeve having a slot in the side thereof into which said slip is adapted to extend, means on the mandrel extending into said slot and engageable with the slip to urge said slip outwardly, locking means on the sleeve engageable with the slip on outward movement of said slip to hold the same in extended position, means on the mandrel engageable with said locking means on ,upward movement of the mandrel, whereby said locking means is releasedv to permit inward movement of said slip, camV means in the sleeve extending to said slot, whereby said slip engaging means is returned to said slot on upward movement of the mandrel.

HARRY WILLIS EVANS. 

